I was having a problem pasting the inline code into my WordPress page for newsletter signups. I could paste the code into the footer, but when I tried to paste the code into the newsletter page, it wouldn't show up. I found a work-around: I went into the block sidebar and typed Constant Contact into the block menu's search bar, and it brought up the block with the shortcode for my pop-up. Now the form shows up on my Newsletter sign-up page. It is the same code as the popup, so it only has a field for email capture: I wanted to use the inline form, which has more fields, but I will count my blessings and be grateful that the form works as is. I hope this helps anyone else who was struggling to get the forms to appear correctly on their site.
Thank you for the information and I am happy to hear that you were able to make it work!